Abstract: A signal processing apparatus includes a first baseline wander correcting unit, provided in a processing path in which a predetermined processing is performed on an input signal, which corrects baseline wander by a feedforward and a second baseline wander correcting unit, provided anterior to the first baseline wander unit, which corrects the baseline wander by a feedback control. The first baseline wander correcting unit derives an amount of baseline wander. Further, it calculates a value corresponding to an average value of the amount of derived baseline wander and fine-adjusts a correction amount of baseline. Then it corrects the baseline wander by using the fine-adjusted baseline amount. The second baseline wander correcting unit calculates a value corresponding to an average value of the amount of baseline wander derived by the baseline wander derivation unit and coarse-adjusts a correction amount of baseline, and corrects the baseline wander by using the coarse-adjusted baseline amount.

Abstract: An apparatus and method for detecting synchronous (SYNC) signals written on a disk memory device is performed by dividing a reproduced SYNC pattern, which includes a predetermined number of symbols, into a plurality of groups. Each of the plurality of groups includes at least one symbol that overlaps a symbol contained in another group. The invention outputs a SYNC detected signal when the symbols of at least one of the divided groups match the symbol of the SYNC pattern. In order to detect the SYNC signal, the invention increases the number of symbols included in each of the divided groups even when a large defect exists in the disk memory device.

Abstract: An apparatus and method for detecting synchronous (SYNC) signals written on a disk memory device is performed by dividing a reproduced SYNC pattern, which includes a predetermined number of symbols, into a plurality of groups. Each of the plurality of groups includes at least one symbol that overlaps a symbol contained in another group. The invention outputs a SYNC detected signal when the symbols of at least one of the divided groups match the symbol of the SYNC pattern. In order to detect the SYNC signal, the invention increases the number of symbols included in each of the divided groups even when a large defect exists in the disk memory device.

Abstract: An extended sync pattern, which is comprised of a pattern portion at the end of a preamble pattern recorded immediately before an original sync pattern in a sector and the original sync pattern, is used in a sync detecting operation in place of the original sync pattern. This sync detecting operation is carried out by receiving read data from the storage medium, repeating an operation of extracting those symbols of data whose quantity coincides with the length of the extended sync pattern from the input data, while shifting an extraction start position by one symbol, and collating the extracted data with a collation pattern coincident with the extended sync pattern every time data extraction is executed.